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Module 1. Care of the patients, its role in the treatment process and organization in the hospital.

Content module 1. Structure and the main tasks of the patients care in general system of the therapeutic profile patients treatment.

Topic 5. Estimation of the patient’s condition and the main parameters of his vital activity. Body temperature, the rules of measurement and registration.

Vital signs are measurements of the body's most basic functions. The four main vital signs routinely monitored by medical professionals and healthcare providers include the following:

• body temperature

• pulse rate

• blood pressure

• respiration rate

Body temperature is a measure of the body's ability to generate and get rid of heat. The body is very good at keeping its temperature within a narrow, safe range in spite of large variations in temperatures outside the body.

B ody temperature is controlled by a hypothalamus.  The hypothalamus controls metabolic processes in the body (such as body temperature, hunger, thirst, fatigue, and stress reactions) by releasing tiny amounts of chemicals that act on other body organs either directly or indirectly.  With respect to body temperature, the hypothalamus acts as a thermostat; it helps maintain body warmth when someone is exposed to cold temperatures by causing shivering and an increased metabolic rate.  When a person is hot (from a fever, from exercise, or from hot weather), it causes sweating and dilation (opening up) of blood vessels in the skin, allowing dissipation of heat. 

Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. This process is one aspect of homeostasis: a dynamic state of stability between a human internal environment and its external environment. If the body is unable to maintain a normal temperature and it increases significantly above normal, a condition known as hyperthermia occurs. The opposite condition, when body temperature decreases below normal levels, is known as hypothermia.

Thermoregulation is an important aspect of human homeostasis. Most body heat is generated in the deep organs, especially the liver, brain, and heart, and in contraction of skeletal muscles. Humans have been able to adapt to a great diversity of climates, including hot humid and hot arid. High temperatures pose serious stresses for the human body, placing it in great danger of injury or even death. For humans, adaptation to varying climatic conditions includes both physiological mechanisms as a byproduct of evolution, and the conscious development of cultural adaptations.

Cooling Reactions

1. Perspiration increases:

• When perspiration (sweat) on the skin evaporates, the process uses some of the body's heat.

• The hypothalamus causes the body to perspire more.

• This increased rate of perspiration then results in more body heat being lost through evaporation.

2. Vasodilation:

• Blood vessels near the surface of the skin loose heat to the environment.

• The hypothalamus causes these blood vessels to become larger (dilate) when the body is too warm.

• When the blood vessels enlarge, they loose heat faster.

• This enlargement causes the skin to have a reddish (flushed) appearance.

Warming Reactions

1. Muscle activity increases:

• When the large muscles of the body are active, heat is produced.

• When the body becomes too cool, the hypothalamus causes the large muscles to contract and relax.

• These contractions and relaxations cycles, called shivers, produce body heat.

2. Blood vessels contract:

• When the body is loosing too much heat, the hypothalamus causes the blood vessels near the surface of the skin to contract (become smaller).

• The blood vessels' decrease in size causes the vessels to loose heat slower than normal.

• The contraction of the blood vessels causes the skin to look pale.

Methods of body temperature measurements

Body temperature is measured using an instrument called a thermometer. The word "thermometer" comes from the Greek word therme (heat) and metre (measure).

There are following general types of thermometers: the glass thermometer, electronic thermometers, and plastic thermometer strip.

T hermometers are calibrated in either degrees Celsius (°C) or degrees Fahrenheit (°F), depending on the custom of the region. The standard in most other countries is degrees Celsius, temperatures in the United States are often measured in degrees Fahrenheit.

A glass thermometer consists of a stem and bulb. The stem (long part) of the thermometer has a hollow shaft running almost the entire length of the stem. The bulb of the thermometer contains a small amount of mercury, a metal that is liquid at ordinary temperatures. The thermometer is designed so that mercury from the bulb can enter the hollow shaft in the stem. If you hold the mercury thermometer so that the bulb is pointed up; however, the mercury will not flow into the shaft. The mercury only enters the shaft if the mercury in the bulb expands and some of the mercury is forced into the shaft. The mercury is cooler than body temperature. When the thermometer bulb is placed next to body tissue, the mercury absorbs some of the body's heat. As the mercury gets warmer, it expands. Since the mercury has no more room in the bulb, some of the mercury is forced into the shaft. More and more mercury is forced into the shaft until the mercury reaches the same temperature as the body tissue and stops expanding. The patient's temperature is determined by measuring how much the mercury expanded.

Reading the glass thermometer (that is, determining the temperature shown) is done by holding the thermometer horizontally by the stem end (the end opposite the bulb) at eye level and rotating the thermometer until the mercury in the shaft can be clearly seen:

A . Hold the thermometer at eye level. You must hold the thermometer at the end of the stem, not the bulb end. (If you held the bulb end, your body heat could cause the temperature reading to increase if the temperature of your fingers is greater than the temperature shown on the thermometer). Normally, the end of the thermometer is held with the fingertips of the right hand as shown in figure A. The thermometer should be held at eye level to make reading easier.